I. Field of the Invention
This invention relates to a tool and a method for aiding in the building or refurbishing process for a gear reduction assembly for an automotive starter. More specifically, the present invention relates to an apparatus for disassembling, reworking and assembling a gear reduction drive system of the type employed by the Chrysler Corporation in its automobile and light truck engines.
II. Description of the Prior Art
Automotive starter motors and drive assemblies have long been known in the trade to present reliability problems in that it is not unusual for the starter system of the automobile to fail or wear out long before the engine requires substantial mechanical work or rebuilding. Many smaller companies have specialized in rebuilding starter systems of this type since a large majority of the parts salvaged from a defective starter assembly may be refurbished at minimum expense. The critical or high-tolerance items may be replaced or remachined in order to provide the required tolerances and reliability. While these starter assemblies may be disassembled, refurbished, and reassembled without requiring a great investment in machine tools, test facilities, etc., it is nevertheless important to minimize the labor required in disassembling and reassembling the starter assemblies if the manufacturer is to maintain a cost-competitive posture when reselling the refurbished starter assemblies. The elimination of only one or two hours of labor and the concommitent expense associated therewith can easily allow a small manufacturer or refurbisher to gain a disproportionately large share of this type of business due to a proportionate reduction in the final cost of the refurbished starter assemblies.
The General Motors Corporation and the Ford Motor Corporation have generally designed their automobile starter assemblies to employ a solenoid actuated starter motor having an armature shaft which directly couples with the flywheel of the engine. In contrast with this design, the Crysler Corporation has for many years employed a gear reduction system between the armature shaft of the starter motor and the flywheel of the engine. In this manner additional torque may be obtained in order to more efficiently initiate the rotation of the engine. While the apparatus in accordance with the present invention could be utilized in the process or refurbishing a General Motors or Ford Starter system, it is nevertheless envisioned that the present apparatus will be more suitably employed during the refurbishing process of the Crysler Corporation type starter motor and gear reduction assemblies.
The inventor, during the course of remanufacturing and refurbishing a large number of these Crysler starter motor assemblies, has expended a great deal of effort in investigating all of the presently utilized systems and machines for refurbishing the Crysler gear reduction starter systems. Typical of the methods presently being used in constructing or refurbishing these gear reduction starter systems is the method presently employed by the Crysler Corporation when initially assembling new starter systems. Crysler presently utilizes hand labor unassisted by automated machines for coupling the gear retainer locks into the appropriate groove within the gear reduction shaft while inserting the gear reduction shaft into the starter drive housing and attaching the main reduction gear and the starter drive gear thereto. This manual process requires a great deal of skill and patience, and it is not unusual for such an assembly process to require 10 to 15 minutes or more. In contrast with this manual assembly system, the use of the apparatus in accordance with the present invention allows the disassembly and reassembly of the gear reduction drive system in less than 3-4 minutes by a semiskilled worker. The obvious time and labor expense savings are obvious when the apparatus in accordance with the present invention is utilized on a high volume basis.
Several United States Patents have been issued for assembly or refurbishings jigs, but none of these references apply to assist in obtaining a solution to the problem at hand. For example, Dail, in U.S. Pat. No. 3,871,055, discloses a foot-actuated press for engaging a horizontal workpiece. The press employs a plunger rod which extends through an opening in a particular work piece in order to engage a movable section thereof. The Dail apparatus, while similar in some respects to the present invention, cannot readily be modified or redesigned in order to perform the alignment, disassembly and reassembly functions of the present invention. Another foot-actuated assembly and work-holding device for machine shops is disclosed by Lelis in U.S. Pat. No. 3,099,875.
Other prior art references do not aid in obtaining information on an apparatus similar in design to the preferred embodiment of the present invention. For example, Hart in U.S. Pat. No. 3,182,388, discloses a device for separating telescoped elements employed in an automotive muffler and tailpipe combination. Wilson, in U.S. Pat. No. 2,680,287, discloses a four-wheeled dolly for supporting motor vehicle parts during the repair and refurbishing process. Holbrook, in U.S. Pat. No. 3,380,149 discloses an apparatus and method for establishing certain pre-determined relationships between the roll mechanisms employed in an automotive odometer. Spytek, in U.S. Pat. No. 3,257,716, discloses an apparatus for extracting the seals carried by a housing of a motor vehicle transmission assembly. Tongurian, in U.S. Pat. No. 3,521,346, discloses a machine for reconditioning and setting up clutches of motor vehicle engines. Okazaki, in U.S. Pat. No. 3,793,718, discloses an apparatus utilized to assist in the mounting and dismounting of a piston through the crankshaft side of the cylinder of a reciprocating internal combustion engine. McDaniel, in U.S. Pat. No. 3,925,872, discloses a tool for aligning the bolt holes in a timing-chain cover with the matching holes in the front of an engine. None of these references provide any assistance in illustrating an apparatus or method which would greatly simplify the disassembly, and reassembly steps involved in refurbishing starter motor gear reduction drive systems of the type referenced herein.
Therefore, the first object of the present invention is to define an apparatus which may be utilized to hold the gear reduction drive assembly during the disassembly, refurbishing, and reassembly steps. The apparatus must assist in holding the constituent parts in relative physical relationship with the required positions and provide certain alignment functions for reducing the skill required to properly integrate the constituent parts. A second object of the present invention is to integrate with this apparatus a foot-actuated mechanism whereby the operator may employ both of his hands to aid in the alignment and assembly process while at the same time controlling the insertion and assembly of the various parts by the use of his feet.